402640645250461 has 4 divisors (see below), whose sum is σ = 423832258158400. Its totient is φ = 381449032342524.

The previous prime is 402640645250453. The next prime is 402640645250477. The reversal of 402640645250461 is 164052546046204.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 402640645250461 - 2³ = 402640645250453 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (402640645250411) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10595806453941 + ... + 10595806453978.

It is an arithmetic number, because the mean of its divisors is an integer number (105958064539600).

Almost surely, 2^{402640645250461} is an apocalyptic number.

It is an amenable number.

402640645250461 is a deficient number, since it is larger than the sum of its proper divisors (21191612907939).

402640645250461 is a wasteful number, since it uses less digits than its factorization.

402640645250461 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21191612907938.

The product of its (nonzero) digits is 5529600, while the sum is 49.

The spelling of 402640645250461 in words is "four hundred two trillion, six hundred forty billion, six hundred forty-five million, two hundred fifty thousand, four hundred sixty-one".